Composite material multilayered membrane with sound insulating and sound absorbing to mitigate impact noise

ABSTRACT

The composite material multilayered membrane of the present invention is sound insulating and sound-absorbent, acting as sound deadening insulation for noise impacts, mainly but not exclusively to be used in flooring, and in particular under the slab in floating floors, with the aim of reducing the transmission of noise into the below room. This membrane includes several layers, which include at least one polymeric monofilament three dimensional mat, at least one resilient mat, and at least one topping layer of waterproofing, breathable or not, tissue. This multilayered membrane with a thickness under a weight of 2 kPa of at least 8 and maximum 15 mm, preferably 10-12 mm, so as to achieve a normalized noise level in the disturbed room Lnw below 50 dB, or an impact insulation class of at least 60 points.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT

Not applicable.

INCORPORATION-BY-REFERENCE OF MATERIALS SUBMITTED ON A COMPACT DISC

Not applicable.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a composite material multilayered membrane,which acts as sound insulating and sound absorbent barrier to mitigateimpact noise in construction, more particularly in floating floorsconstruction.

2. Description of Related Art Including Information Disclosed Under 37CFR 1.97 and 37 CFR 1.98.

Definitions. The term “floating floor” indicates a floor formed by afloating, at least 1 inch thick, slab, resting on top of a generallyelastic panel which separates it from the subfloor, in order to form anoscillating system which absorbs the impact energy. The term “impactnoise” refers to:

-   -   a percussion on vertical walls or floors caused mainly by        pounding or falling objects;    -   a friction caused by furniture moving or other;    -   a vibration due to machinery or equipment that are in direct        contact with the walls or the floors.        This impact noise spreads directly through the solid structures        of the building, not only in the underlying room which is the        most exposed, but also in the other ones, more or less distant        from the one in which the phenomenon occurred, according to the        structural characteristics of the building.

FIELD OF APPLICATION

Conventionally, users of spaces in residential buildings, feel the needto isolate themselves from the noise of their neighbors, in particularfrom the impact noise from upper floors. Although many engineers,designers and manufacturers in recent years have adopted sound controlsystems, using materials readily available on the market, such as rubberrolls or panels, cork rolls or panels, woven polypropylene orpolyethylene rolls and other similar products, only a few of thesesolutions are technically adequate and in compliance with tests andcertifications relating to sufficient dynamic stiffness. Indeed, veryoften this parameter, that is the value which defines the ability of aninsulating membrane subjected to a dynamic solicitation to deformelastically, is unknown, or these values are not supplied by themanufacturers, and then on continue to take not technically correctapplication systems. It must be considered that any source of sound istransformed into a source of noise if it becomes a source of disturbanceto other people, so insufficient acoustic soundproofing is considered adefect of the building. Under the civil law relating to business, it isthe vendor that must repair the defeat or reduce the price of thebuilding.

In order to decrease the transmission of noise impact, as known, variouselastic acoustic products were then developed, predominantly tocompletely isolate and solidify the floor from the rest of the rigidstructures. There are numerous examples of national legislation layingdown restrictions on the transmission of noise between consecutiverooms, using the parameters defined by organizations and groups tomeasure the noise in the disturbed room when a specific tapping machineis running into the room above. The legislature has thus defined thelimits of noise to be observed and then the acoustic requirements ofbuildings, especially of the floors between two consecutive levels. Overthe years, legislative limits have become gradually more restrictive andas seen, several devices have been developed by different companies tosolve this problem. These devices will function when their elasticity isenergized by a mass that acts on them, and thus are preferably usedunder floating floors. However, in some cases, such as in buildingrenovation, it is not always possible to make a floor for space or loadmatters, so some devices may be used directly under the ceramic tile orwood parquet.

DESCRIPTION OF PRIOR ART

A search has been conducted in the field of acoustic membranes andimpact noise insulation devices, which made it possible to trace atleast the following documents:

-   -   D1 ITTV2006A000054 (Cais et al.)    -   D2 DE1224020 (Mueller)    -   D3 FR1539907 (Saint Gobain)    -   D4 FR2056275 (Saint Gobain)    -   D5 FR2517728 (Strati France)    -   D6 FR2824094 (Siplast)    -   D7 FR2775013 (Nortene Technologies)    -   D8 JP7166617 (Terayama et al.)    -   D9 JP2013656 (Kuroda)

D1 describes a soundproof membrane for floors, intended to be useddirectly below the slab in floating floors or directly under the floorfinishing to reduce the transmission of impact noise between twoconsecutive levels of a building, which consists of a set of mats, madefrom monofilament fibers or polymers, or alveolar materials with atleast one protective waterproofing film and characterized by the factthat this multilayer of mats defines a space for the most part filledwith air, called “air foil”, with a thickness of at least 6 and at most20 mm, and preferably 10-15 mm. The main purpose is to develop asound-floor membrane through which it is possible to obtain aparticularly effective soundproofing between consecutive levels of abuilding by allowing to contain noise from the upper floors within atolerance level to be provided under 58 dB, conventionally calculated,by maintaining the advantages of a single product to be used directlyunder the floor finishing or under the slab in floating floors.

D2 describes the same principle with one layer of soundproofing panels,made up of a glass fiber felt of at least 130 grams per square meter,topped by a rigid layer of bitumen or resin.

D3 introduces the use of felt in a glass fiber with specificcharacteristics such as fiber length of at least ten centimeters, fiberdiameter from 10 to 40 μm, to form an insulating felt weighing from 150to 300 g/m², and D4 describes the use of a felt in a glass fiber under afloating floor to isolate the tapping noise.

D5 introduces the use of felt in a glass fiber with specificcharacteristics, combining an elastic material to a load bearing andsound waves distributor panel, to be used directly below the floorfinishing, avoiding to use the floating floor.

D6 includes a lower support and an upper surface comprising a felt orother material with characteristics of resilience, possibly associatedwith an impermeable film and a thin metal foil with density of at least150 g/m².

D7 describes a sound material comprising a first layer of fabricweighing between 200 and 1000 g/m², preferably between 350 and 400 g/m²,a second layer of non woven fabric weighing between 40 and 200 g/m²,preferably between 60 and 150 g/m², where both the two layers are bondedby a plastic reticular structure.

D8 suggests a material to reduce impact noise on a floor. It is made upof accommodation cavities forecast in a plane next to the other in a netof non woven polypropylene or polyester, and silica particles internallydistributed in such a way to form a structure with damping effect.

D9 describes a structure to isolate the noise between floors. It is alayered structure, in which below the top layer it is coated athree-dimensional layer of synthetic threads.

In the market, there are also known materials in monofilaments mats usedto mitigate the impact noise between floors. For example, in the sitewww.colbond-usa.com, Colbond company describes the product Acousti-MatII™ and III and the product Enkasonic E™. These are products in nylonfilaments three dimensional mats, with thickness comprised between 6 mmand 20 mm, and with density between 42.6 kg/m³ and 88 kg/m³.

In the site www.keenebuilding.com, Keene Building Products, describessound mats for floating floors named Quiet Qurl 55-025™, 6 mm thick, andQuiet Qurl 60-040™, 10 mm thick, with a polyester topping joined to athree dimensional polypropilene extruded threads mat.

It is therefore reasonable to consider as known a flooring impact sounddeadening membrane, or the membrane or the multilayered structure,suitable to reduce the impact sound, which is comprised of at least:

-   -   one layer of mat as a three dimensional extruded polymeric        monofilament mat;    -   a non woven polymeric tissue; and    -   a felt joined to a waterproofing film.

DISADVANTAGES

The opinion of the applicant is that the above described devicesunlikely meet the requirements to achieve an optimum level of acousticcomfort.

More specifically, the state of the art shows like all known solutionsby themselves are not exempt from drawbacks and limitations in relationto the specified parameters and user requirements. More in detail, theabove described solutions, while suitable to contain the impact noiselevel in the disturbed room to values lower than 70 dB, in the opinionof the applicant, those solutions are sufficient in itself to reduce theintensity of the noise levels prescribed by legislation; however, thesolutions are not sufficient to reduce it at levels lower than 55 dB,which correspond to an optimum acoustic comfort. As to the products useddirectly under the floor, there are no solutions that meet the needs ofacoustic comfort.

It is certainly true that the solution described in D1, proposed a sounddeadening membrane with which it is possible to obtain normalized impactsound levels of 51 dB in the disturbed room, with thicknesses between 6and 20 mm, preferably from 10 to 15 mm. It is defined in particular acritical thickness between 10 and 12 mm, composed by many layers offibrous materials with low rigidity containing a great amount of air.These values satisfy the legislative limits, but they don't allow anadequate margin of safety like the one obtainable, with thicknessesbetween 10 and 12 mm, with the object of this invention. In particularfor the light wooden floors, which are the most difficult to solveacoustically, it is necessary to provide products that can get, in astandard test, noise levels Lnw below 50 dB in the disturbed room, or animpact insulation class of at least 60 points.

For the above described reasons, there is a need for businesses,particularly in the specific field, to find out alternative solutions,more effective, compared to the solutions present in current timemarket. One purpose of this is invention is also to overcome the abovedescribed disadvantages.

BRIEF SUMMARY OF THE INVENTION

This and other aims are achieved with this invention according to thefeatures of the attached claims solving the above exposed problems bymeans of a composite material multilayered membrane, being soundinsulating and sound-absorbent, which acts as sound deadening insulationfor noise impacts, mainly but not exclusively designed to be used in theflooring, and in particular under the slab in floating floors, with theaim of reducing the transmission of noise into the below room. Thismembrane comprises several layers, which are at least one polymericmonofilament three dimensional mat, at least one resilient mat, at leastone topping layer of waterproofing, breathable or not, tissue. Thismultilayered membrane with a thickness under a weight of 2 kPa of atleast 8 and maximum 15 mm, preferably 10-12 mm, so as to achieve anormalized noise level in the disturbed room Lnw below 50 dB, or animpact insulation class of at least 60 points.

Aims:

In this way, through the considerable creative contribution whose effecthas achieved a considerable technical progress, some goals and benefitscan be reached.

A first aim is to achieve a particular impact noise insulating membranethat can achieve the sound insulation between consecutive levels of abuilding, allowing to reduce the disturbing noises coming from the aboveroom within a level that complies with the constraints imposed bylegislation with a wide safety margin.

A second purpose is to provide a solution that can be used in everyapplication that requires impact noise insulation, where the weightwhich urges the structure is less than 500 kg/m².

A third purpose of the invention is to achieve a very effective impactsound insulating membrane in a single product obtained directly in thefactory of production without the need for installation of morematerials together or of more layers of membrane itself.

A fourth aim is to achieve an effective impact noise insulating membranewith a waterproofing finishing fabric that can prevent the penetrationof liquid cement or gypsum concrete through the product during the slabpouring phase, which otherwise might affect the sound insulationproperties of the membrane.

A fifth goal is to create a membrane, effectively insulating towardsimpact noise, with a waterproofing and breathable finishing fabric,which could bring through its breathability to a more rapid drying ofthe slab, lowering the perfection time of the work.

A sixth objective is to achieve a multilayered membrane, effectivelyinsulating towards impact noise, with a finishing fabric larger than thebelow layers along the entire length of the roll, with a bituminous orbutyl or bi-adhesive curb, protected by a silicone release paper, whichwould seal the connections between different rolls in opera, without theneed to give to jobsite staff specific instructions for installation, orto use more tapes. The sealing between two consecutively laid down rollsis ensured in order to avoid, during slab pouring phase, liquid cementor gypsum penetrating through the joints and affecting the sounddeadening features of the membrane.

A seventh aim is to achieve a multilayered membrane, effectivelyinsulating towards impact noise, that can contribute to thermalinsulation of the assembly.

In particular, it has been possible to obtain a more integrated andcompact structure, with a good technologic content and relatively lowcost. These and other advantages will appear with the subsequentdetailed description of some preferential solutions, with the help ofthe attached schematic drawings, whose details are not to be intendedrestrictive but only illustrating.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a perspective view of a first solution of multilayeredcomposite materials membrane.

FIG. 2 is a perspective view of a second solution of multilayeredcomposite materials membrane.

FIG. 3 is another perspective view of a third solution of multilayeredcomposite materials membrane.

DETAILED DESCRIPTION OF THE INVENTION

The invention relates to a multilayered composite material membrane (10,20, 30), which acts as insulating barrier towards impact noise, which iscomposed by multiple layers and in particular of at least one polymericmonofilament three dimensional mat (101, 102, 103), at least oneresilient mat (201, 202, 203), with at least one layer of waterproofing,breathable or not, layer (301, 302, 303), permeable to vapor or not,with a total thickness under a weight of 2 kPa of at least 8 mm andmaximum 15 mm, preferably between 10 and 12 mm.

The demonstration of the effectiveness of the solutions covered by thisinvention can be easily demonstrated using a semi-anechoic chamberequipped with sound level meter. The ceiling of this room consists of abrick cement floor 200 mm thick, the walls of this room are in 200 mmthick full bricks. The multilayered impact sound deadening membrane itis laid down on the top of this ceiling, over it is applied a 50 mm sandcement slab, metal lathe reinforced, top finished with ceramic tiles.Over the tiles a normalized tapping machine working. The test isperformed according to EN ISO 717-2 and EN ISO 140-8, adapted inrelation to the size of the receiving room (1000 mm per 1000 mm per 1000mm) and the size of the sample in analysis (600 per 600 mm).

The acoustic performance of the material is measured by the normalizednoise level (Lnw) transmitted in the receiving room or impact insulationclass (IIC). These parameters are calculated according to the standardon the basis of interpretation of data acquired by the sound levelmeter, connected to a microphone positioned at the center of thereceiving room at half of its height.

In a first preferred embodiment of the invention (FIG. 1), it isforeseen that under the 50 mm tiled floating slab weighing 170 kg/m²,corresponding to a pressure of 1.67 kPa on lay down the multilayeredmembrane (10), which is composed by one three dimensional polypropylenemonofilaments, entangled and welded where they cross, wavy shaped withparallel channels structure mesh (101), weighing 550 g/m², by a needledand resined polyester mat, with 6 to 18 dtex polyester fibers, (201)weighing 250 g/m² and top finished with a low density polyethylene (301)weighing 50 g/m². In such conditions, the transmission of tapping noisethat in the absence of an interposed material is greater than 80 dB, isreduced to a normalized sound level Lnw of 48 dB, corresponding to anImpact Insulation Class of 62. In this configuration the multilayeredmembrane has an apparent dynamic stiffness of 12 MN/m³ according to EN29052.

In a second preferred embodiment of the invention, (FIG. 2) it isforeseen that under the 50 mm (1.5″) tiled floating slab weighing 170kg/m², corresponding to a pressure of 1.67 kPa or 34.82 psf on lay downthe multilayered membrane (20), which is composed by one threedimensional polipropylene threads mesh (102), entangled and welded wherethey cross, cuspated shaped, weighing 550 g/m², by a needled and resinedpolyester mat, with 6 to 18 dtex polyester fibers, (202) weighing 250g/m², and top finished with polypropylene breathable waterproofingmembrane (302) weighing 150 g/m². In such conditions, the transmissionof tapping noise that in the absence of an interposed material isgreater than 80 dB, is reduced to a normalized sound level Lnw of 45 dB,corresponding to an Impact Insulation Class of 65. In this configurationthe multilayered membrane has an apparent dynamic stiffness of 9 MN/m³according to EN 29052.

In a third preferred embodiment of the invention, (FIG. 3) it isforeseen that under the 50 mm (1.5″) tiled floating slab weighing 170kg/m², corresponding to a pressure of 1.67 kPa or 34.82 psf on lay downthe multilayer membrane (30) which is composed by one three dimensionalpolipropylene threads mesh (103), entangled and welded where they cross,cuspated shaped, weighing 550 g/m². This three dimensional mesh iscomprised between a sandwich of two mats made up of needled and resinedpolyester (203 a and 203 b), whose polyester fibers are from 6 to 18dtex, weighing each one 250 g/m², and in which at least one of thepolyester mats are coupled with a waterproofing breathable polypropylenemembrane (303 a) 100 g/m² weighing. In such conditions, the transmissionof tapping noise that in the absence of an interposed material isgreater than 80 dB, is reduced to a normalized sound level Lnw of 42 dB,corresponding to an Impact Insulation Class of 68. In this configurationthe multilayered membrane has an apparent dynamic stiffness of 8 MN/m³according to EN 29052.

In the described solutions, multilayered impact sound deadening membrane(10, 20, 30) is composed by the resilient mat (201, 202, 203 a, 203 b)that is a needled and resined polyester synthetic fibers mat, with 3.3to 20 dtex fibers and preferably 6 to 17 dtex fibers, and with a totalweight comprised between 150 e to 450 g/m2, preferably comprised between200 and 300 g/m². As for at least one of the finishing layers, (301 302,303), it is in low density polyethilene weighing from 10 to 100 g/m².

Multilayered membrane (10, 20, 30) can have a finishing layer (301, 302,303), in waterproofing breathable polypropylene membrane, weighing from50 to 200 g/m², preferably from 80 to 160 g/m² with water penetrationresistance higher than 2 meters (mt) of water column according to EN20811, with a vapor diffusion coefficient sd comprised between at least0.01 and at most 0.05 according to EN ISO 12572.

Finishing breathable waterproofing layer (301, 302, 303) can besides bein polyester.

Furthermore the impact sound deadening membrane (10, 20, 30) can have afinishing layer in waterproofing breathable membrane (301, 302, 303) atleast 8 cm larger than the other layers along the entire length of theroll, forming a selvedge equipped with a minimum 15 mm wide bituminousor butyl or bi-adhesive strip, protected by a silicone release paper,which is used to seal the connections between different rolls in opera.

LEGEND

-   -   (10, 20, 30) multilayer impact sound deadening membrane    -   (101, 102, 103) three dimensional polypropylene threads mesh        entangled and welded where they cross    -   (201, 202, 203 a, 203 b) resilient mat in polyester fibers    -   (301, 302, 303) finishing waterproofing membrane

1. A multilayered composite material membrane, being sound insulatingand sound absorbent towards impact noise in flooring and thermalinsulation auxiliary, the membrane comprising: at least one3-dimensional polymeric monofilaments mat; at least one resilient mat;and at least one waterproofing, finishing layer, wherein said resilientmat is a synthetic fibers mat coupled with at least one waterproofingfinishing layer, the mats and layer having a total thickness, under aweight of 2 kPa, comprised between at least 8 mm and at most 15 mm. 2.The multilayered composite material membrane according to claim 1,having a thickness under a weight of 2 kPa between at least 10 mm and12.5 mm.
 3. The multilayered composite material membrane according toclaim 1, wherein the 3-dimensional polymeric monofilaments mat iscomprised of polypropylene based extruded filaments, entangled andwelded at crossings, having a weight comprised between 400 g/m² and 700g/m² and having a thickness under a weight of 2 kPa comprised between atleast 8 and at most 10 mm.
 4. The multilayered composite materialmembrane according to claim 1, wherein the 3-dimensional polymericmonofilaments mat is comprised of polypropylene based extrudedfilaments, entangled and welded at crossings, being wavy shaped withparallel channels structure.
 5. The multilayered composite materialmembrane according to claim 1, wherein the three dimensional polymericmonofilaments mat is comprised of polypropylene based extrudedfilaments, entangled and welded at crossings and having a cuspatedshape.
 6. The multilayered composite material membrane according toclaim 1, wherein the three dimensional polymeric monofilaments mat iscomprised of polyester based extruded filaments, entangled and welded atcrossings.
 7. The multilayered composite material membrane according toclaim 1, wherein the three dimensional polymeric monofilaments mat iscomprised of polyammide based extruded filaments, entangled and weldedat crossings.
 8. The multilayered composite material membrane accordingto claim 1, wherein the resilient mat is comprised of a non woven fabricof synthetic fibers.
 9. The multilayered composite material membraneaccording to claim 1, wherein the resilient mat is comprised of 3.3 to20 dtex synthetic polyester fibers, needled and resined.
 10. Themultilayered composite material membrane according to claim 1, whereinthe resilient mat is comprised of 6 to 17 dtex synthetic polyesterfibers, needled and resined.
 11. The multilayered composite materialmembrane according to claim 1, wherein at least one resilient mat iscomprised of synthetic polyester needled and resined fibers, having aweight between at least 150 g/m² and at most 450 g/m².
 12. Themultilayered composite material membrane according to claim 1, whereinthe at least one resilient mat is comprised of synthetic polyesterneedled and resined fibers, having a weight between at least 200 g/m²and at most 300 g/m².
 13. The multilayered composite material membraneaccording to claim 1, wherein the at least one waterproofing finishinglayer is comprised of low density polyethilene, weighing between atleast 10 g/m² and at most 80 g/m².
 14. The multilayered compositematerial membrane according to claim 1, wherein the at least onewaterproofing finishing layer is comprised of a waterproofing and vaporpermeable synthetic spun bonded tissue.
 15. The multilayered compositematerial membrane according to claim 1, wherein the at least onewaterproofing finishing layer is comprised of waterproofing and vaporpermeable synthetic spun bonded tissue weighing between at least 90 g/m²and at most 160 g/m², with water penetration resistance higher than 2meters of water column according to EN 20811, with a vapor diffusioncoefficient sd comprised between at least 0.01 and at most 0.05according to EN ISO
 12572. 16. The multilayered composite materialmembrane according to claim 1, wherein the at least one waterproofingfinishing layer is comprised of waterproofing and vapor permeablepolypropylene based spun bonded tissue.
 17. The multilayered compositematerial membrane according to claim 1, wherein the at least onewaterproofing finishing layer is comprised of waterproofing and vaporpermeable polyester based spun bonded tissue.
 18. The multilayeredcomposite material membrane according to claim 1, wherein the at leastone waterproofing finishing layer is comprised of a waterproofing andvapor permeable synthetic spun bonded tissue at least 8 cm larger thanthe monofilament mat and the resilient mat, forming a selvedge equippedwith a minimum 15 mm wide butyl strip, protected by a release siliconepaper.